SLC16A2 and hyperinsulinemic hypoglycemia, familial, 4: Data from the International MCT8 Deficiency Registry—a prospective registry of parents and physicians caring for patients with MCT8 deficiency—showed that 58% (18/31) of parents reported knowledge of MCT8 deficiency among medical professionals they encountered to be “bad” or “very bad”, illuminating the need for increased awareness and education of HCPs (4).